A related art position detector device is, for example, described in the following Patent Document 1. The position detector device described in Patent Document 1 includes: a pair of plate-shaped magnetic bodies: a pair of magnets which are located between the pair of magnetic bodies and have different magnetic field directions; a rotating member which causes the pair of magnetic bodies and the pair of magnets to rotate in accordance with the operated amount of an operating grip; and a magnetic detector unit which is disposed in an inner side of a closed magnetic circuit formed by the pair of magnetic bodies and the pair of magnets and which detects a change in leakage magnetic field caused inside the closed magnetic circuit when the rotating member causes rotation.